Association between underlying medical conditions and fatality risk in H7N9-infected patients: a meta-analysis / 预防医学

ABSTRACT

Objective The objective of our study was to conduct meta-analyses that examined the association between H7N9-infected case-fatality risk (CFR) and underlying medical conditions (UMCs) by adjusting some potential factors variables. Methods The articles of observational studies and randomized controlled clinical trials (RCT) on the association between UMCs and the CFR of H7N9-infected patients were collected and selected according to inclusion and exclusion criteria. Meta-analysis was performed to calculate odds ratio (OR) or adjusted OR (AOR) and 95％ confidence interval (CI) to assess the association between H7N9-infected CFR and UMCs. Results Among 1934 screened articles, we identified 14 articles reporting the CFR of H7N9-infected patients based on UMCs data. The pooled summary estimates from these studies indicated that UMCs significantly increased the risk of death in H7N9 patients (OR=2.20, 95％CI 1.76-2.76) . Subgroup analyses showed chronic respiratory diseases (CRD, OR=4.43, 95％CI 1.73-11.31), immuno-suppressive disorders (ISD, OR=4.65, 95％ CI1.48-44.70), and two UMCs and above (OR=2.13, 95％ CI 1.26-5.97) were significantly associated with H7N9-infected CFR; while 60 years old and above (AOR=4.83, 95％CI 1.29-18.09), male (AOR=2.35, 95％CI 1.03-5.39), time intervals to oseltamivir treatment (over 5 days) (AOR=5.74, 95％ CI 1.15-28.66) and hospitalization (over 8 days) (AOR=2.72, 95％CI 1.20-6.15), and initially bilateral lungs infection (AOR=7.95, 95％CI 1.56-40.41) of UMCs patients who died from H7N9 infection are much greater compared with non-UMCs. Stratification analyses confirmed statistically significant increasing effects of CFR were observed in 60 years old and above (AOR=2.20, 95％ CI 1.12-4.30) , time intervals to oseltamivir treatment (over 5 days) (AOR=3.19, 95％CI 1.56-6.53), and initially bilateral lungs infection (AOR=3.48, 95％CI 1.74-6.95) compared with 0-59 years old, time intervals to oseltamivir treatment (5 days and below), and initially single lung infection respectively in H7N9-infected patients with UMCs. Conclusions We find that only CRD, ISD, and two UMCs and above are associated with increased risk of death in H7N9-infected patients. We also suggest that a high CFR is associated with 60 years old and above, delayed antiviral treatment, and initially bilateral lungs infection in H7N9-infected patients with UMCs.